The present invention relates to a vehicle underfloor structure.
One conventional vehicle underfloor structure employs an under cover closing the underside of the engine room. This under cover is made as flat as possible, and formed with louvers (14a in FIG. 28) for discharging the hot air inside the engine room. Japanese Utility Model Provisional Publication No. 60-105526 shows a similar conventional example.
In the conventional structure, the hot air discharged from the louvers tends to slow down the underfloor air stream as shown by velocity profiles u1-u4 in FIG. 28 while the rear wheels receive the relatively fast outside air streams.